Labcorp Launches Expanded DPYD Test to Identify Cancer Patients at Risk for Severe Chemotherapy Side Effects

New pharmacogenomic test detects all DPYD variants recommended by the Association for Molecular Pathology to support safer, more personalized cancer treatment

BURLINGTON, N.C., May 28, 2026 /PRNewswire/ -- Labcorp (NYSE: LH), a global leader of innovative and comprehensive laboratory services, today announced the availability of its expanded DPYD Genotyping test to help identify cancer patients who may be at increased risk for severe or life-threatening side effects from fluoropyrimidine chemotherapy. Labcorp now offers genotype testing for all DPYD Tier 1 and Tier 2 variants recommended by the Association for Molecular Pathology (AMP).

"Advances in pharmacogenomics are reshaping cancer care," said Marcia Eisenberg, Ph.D., chief scientific officer at Labcorp. "Our expanded DPYD test identifies patients at risk for severe toxicity before treatment begins, supporting safer, more personalized care. This expansion also strengthens Labcorp's pharmacogenomics and oncology portfolio, complementing the company's hereditary cancer testing, screening, diagnostic and precision oncology offerings to support more personalized cancer care across the patient journey."

Addressing a Significant Risk in Chemotherapy
Some patients experience preventable severe toxicity and death from chemotherapy intended to treat their cancer. Fluoropyrimidines, including 5-fluorouracil (5-FU) and capecitabine, are chemotherapy agents widely used to treat cancers including colorectal, pancreatic, upper gastrointestinal, breast, and head and neck. However, approximately 9% of patients carry a DPYD variant that can impair their ability to break down these drugs, increasing the risk of severe toxicity, and contributing to an estimated 1,300 deaths in the United States each year from 5-FU toxicity.

The DPYD gene encodes the enzyme DPD, which metabolizes more than 80% of 5-FU. Patients with reduced or absent DPD activity can experience serious, potentially life-threatening side effects, including diarrhea, neutropenia and neurotoxicity when exposed to 5-FU or capecitabine.

Updated U.S. Food and Drug Administration (FDA) product labeling for 5-FU and capecitabine includes a Boxed Warning about the risk of severe adverse reactions or death in patients with complete DPD deficiency. The FDA also advises testing for DPYD variants before treatment with 5-FU or capecitabine unless immediate treatment is necessary and recommends avoiding use of these drugs in patients with certain homozygous or compound heterozygous DPYD variants associated with complete DPD deficiency. Recent updates to National Comprehensive Cancer Network (NCCN) guidelines for colon cancer and other relevant indications reference these Boxed Warnings and the recommendation for DPYD testing. Clinical Pharmacogenomics Implementation Consortium (CPIC) guidelines further recommend adjusting or avoiding treatment based on a patient's DPYD metabolizer status as determined by DPYD testing.

Building on Leadership in Pharmacogenomics
Labcorp has offered DPYD testing since 2006 and offers pharmacogenomic testing across multiple specialty areas, including oncology, cardiology, neurology, women's health, pain management, gastroenterology and transplantation, helping providers use genetic information to tailor therapy, reduce preventable harm and support more personalized care.

The test is available to clinicians through Labcorp. For more information, visit https://www.labcorp.com/tests/512275/dpyd-genotyping

About Labcorp
Labcorp (NYSE: LH) is a global leader of innovative and comprehensive laboratory services that helps doctors, hospitals, pharmaceutical companies, researchers and patients make clear and confident decisions. We provide insights and advance science to improve health and improve lives through our unparalleled diagnostics and drug development laboratory capabilities. The company's nearly 71,000 employees serve clients in approximately 100 countries, provided support for more than 85% of the new drugs and therapeutic products approved by the FDA in 2025 and performed more than 750 million tests for patients around the world. Learn more at www.labcorp.com.

SOURCE Labcorp